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A323003
Numbers k such that 357*2^k+1 is prime.
1
2, 3, 7, 8, 10, 14, 18, 23, 26, 27, 35, 44, 46, 50, 55, 56, 59, 67, 80, 115, 138, 248, 280, 319, 372, 416, 454, 624, 662, 686, 702, 707, 806, 847, 866, 1422, 1930, 2115, 2835, 3283, 3358, 3510, 4420, 9284, 10007, 10990, 13775, 14466, 14558, 16099, 16319
OFFSET
1,1
LINKS
Jeppe Stig Nielsen, Table of n, a(n) for n = 1..79 (terms n = 1..77 from Robert Price)
Ray Ballinger, Proth Search Page
Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for 300 < k < 600
Eric Weisstein's World of Mathematics, Proth Prime
MAPLE
select(k->isprime(357*2^k+1), [$1..1000]); # Muniru A Asiru, Jan 02 2019
MATHEMATICA
Select[Range[1000], PrimeQ[357*2^# + 1] &] (* Robert Price, Jan 01 2019 *)
CROSSREFS
Sequence in context: A028808 A029718 A206821 * A051468 A002274 A329783
KEYWORD
nonn,hard
AUTHOR
Robert Price, Jan 01 2019
STATUS
approved